Heat pump assembly with a chiller for battery-powered vehicles and methods of operating the heat pump assembly

Abstract

A heat pump assembly with a chiller for battery-powered vehicles, having a refrigerant circuit with a compressor, a heating condenser, a refrigerant valve with an expansion function, an ambient heat exchanger, at least one evaporator with an associated refrigerant valve with an expansion function, as well as a 3/2-way refrigerant valve with an expansion function disposed in parallel to the evaporator with a refrigerant path via a chiller bypass and a refrigerant path via a chiller.

The invention claimed is: 
     
       1. A heat pump assembly with a chiller for battery-powered vehicles, comprising a refrigerant circuit with a compressor, a heating condenser, a first refrigerant valve with an expansion function, an ambient heat exchanger, at least one evaporator with an associated second refrigerant valve with an expansion function, as well as a first 3/2-way refrigerant valve with an expansion function disposed in parallel to the at least one evaporator with a refrigerant path via a chiller bypass and a refrigerant path via the chiller, wherein an ambient heat exchanger bypass with a third refrigerant valve with an expansion function is disposed upstream of the chiller between the heating condenser and the first refrigerant valve with the expansion function, and further comprising a battery coolant circuit with a first coolant pump, the chiller, a battery heat exchanger, and a battery cooling radiator, wherein a battery cooler radiator bypass with an auxiliary coolant heater is disposed in parallel to the battery cooling radiator via a first 3/2-way coolant valve in the battery coolant circuit, and having a drive train coolant circuit with a second coolant pump, a drive train cooler, and a drive train cooling radiator, wherein a fluid connection is formed in parallel to the drive train cooling radiator from the drive train coolant circuit to the battery cooler radiator bypass of the battery coolant circuit, and that a battery heat exchanger bypass with a second 3/2-way coolant valve is formed for connecting the drive train coolant circuit to the chiller of the battery coolant circuit. 
     
     
       2. The heat pump assembly according to  claim 1 , wherein an air PTC is disposed in an air conditioning device in addition to the heating condenser for heating air for a vehicle cabin. 
     
     
       3. The heat pump assembly according to  claim 1 , wherein a drive train loop is formed with a second 3/2-way refrigerant valve in parallel to the drive train cooling radiator. 
     
     
       4. The heat pump assembly according to  claim 1 , wherein the ambient heat exchanger, the drive train cooling radiator, and the battery cooling radiator are combined in one radiator unit. 
     
     
       5. The heat pump assembly according to  claim 1 , wherein a refrigerant collector is disposed upstream of the compressor in the refrigerant circuit. 
     
     
       6. The heat pump assembly according to  claim 1 , wherein R134a or R1234yf is used as a refrigerant in the refrigerant circuit. 
     
     
       7. A method of operating the heat pump assembly according to  claim 1  for actively cooling a vehicle cabin, for homogenizing a temperature distribution of a battery and for passively cooling a drive train at ambient temperatures of more than 30° C., wherein a refrigerant is condensed downstream of the compressor in the ambient heat exchanger, is expanded in the second refrigerant valve with the expansion function and is evaporated in the at least one evaporator with absorption of heat from air for cooling the vehicle cabin and is directed to the compressor, wherein the battery coolant circuit with the first coolant pump, the battery heat exchanger and the battery cooler radiator bypass is operated in recirculation mode without heating or cooling, and the drive train coolant circuit with the second coolant pump, the drive train cooler and the drive train cooling radiator is operated for passive cooling. 
     
     
       8. A method of operating the heat pump assembly according to  claim 1  for actively cooling a vehicle cabin, for actively cooling a battery and for passively cooling a drive train at ambient temperatures of more than 30° C., wherein a refrigerant is condensed downstream of the compressor in the ambient heat exchanger and then a partial flow is expanded in the second refrigerant valve with the expansion function and evaporated in the at least one evaporator with absorption of heat from air for cooling the vehicle cabin and is directed to the compressor, and a partial flow is expanded in the first 3/2-way refrigerant valve with the expansion function and is evaporated in the chiller with absorption of heat from the battery coolant circuit for cooling the battery and is directed to the compressor, wherein the battery coolant circuit with the first coolant pump, the chiller and the battery heat exchanger is operated in an active cooling mode and the battery cooler radiator bypass is operated without heating and the drive train coolant circuit with the second coolant pump, the drive train cooler and the drive train cooling radiator is operated for passive cooling. 
     
     
       9. A method of operating the heat pump assembly according to  claim 1  for actively cooling a vehicle cabin, for passively cooling a battery and for passively cooling a drive train at ambient temperatures of more than 30° C., wherein a refrigerant is condensed downstream of the compressor in the ambient heat exchanger, is expanded in the second refrigerant valve with the expansion function and is evaporated in the at least one evaporator with absorption of heat from air for cooling the vehicle cabin and is directed to the compressor, wherein the battery coolant circuit from the first coolant pump, via the chiller, the battery heat exchanger and the battery cooling radiator is operated for passive cooling, and the drive train coolant circuit with the second coolant pump, the drive train cooler and the drive train cooling radiator is operated for passive cooling. 
     
     
       10. A method of operating the heat pump assembly according to  claim 1  for a reheating mode of a vehicle cabin, for passively cooling a battery and for passively cooling a drive train at ambient temperatures of more than 15° C., wherein a refrigerant releases heat downstream of the compressor in the heating condenser, is then expanded in the first refrigerant valve with the expansion function to a medium pressure level and releases heat in the ambient heat exchanger, is expanded in the second refrigerant valve with the expansion function to a low-pressure level and is evaporated in the at least one evaporator with absorption of heat from air and is directed to the compressor, wherein the battery coolant circuit from the first coolant pump, via the chiller, the battery heat exchanger and the battery cooling radiator is operated for passive cooling, and the drive train coolant circuit with the second coolant pump, the drive train cooler and the drive train cooling radiator is operated for passive cooling. 
     
     
       11. A method of operating the heat pump assembly according to  claim 1  for a reheating mode of a vehicle cabin, for actively cooling a battery and for actively cooling a drive train at ambient temperatures of more than 0° C., wherein a refrigerant releases heat downstream of the compressor in the heating condenser, is then expanded in the first refrigerant valve with the expansion function to a medium pressure level and absorbs heat in the ambient heat exchanger, and then, a partial flow is expanded in the second refrigerant valve with the expansion function and evaporated in the at least one evaporator with absorption of heat from air and is directed to the compressor, and a partial flow is expanded in the first 3/2-way refrigerant valve with the expansion function and evaporated in the chiller with absorption of heat from the battery coolant circuit and from the drive train coolant circuit and is directed to the compressor, wherein the battery coolant circuit and the drive train coolant circuit are connected to each other and coolant flows from the first coolant pump, via the chiller, the battery heat exchanger, the first 3/2-way coolant valve, the second coolant pump, the drive train cooler to the first coolant pump. 
     
     
       12. A method of operating the heat pump assembly according to  claim 1  for a reheating mode of a vehicle cabin at ambient temperatures of more than 0° C., wherein a refrigerant releases heat downstream of the compressor in the heating condenser, is then expanded in the first refrigerant valve with the expansion function to a medium pressure level and absorbs heat in the ambient heat exchanger, and then, a partial flow is expanded in the second refrigerant valve with the expansion function and evaporated in the at least one evaporator with absorption of heat from air and is directed to the compressor, and a partial flow is expanded in the first 3/2-way refrigerant valve with the expansion function and evaporated in the chiller with absorption of heat from the battery coolant circuit and is directed to the compressor, wherein, in the battery coolant circuit, coolant flows from the first coolant pump, via the chiller, the second 3/2-way coolant valve and the battery heat exchanger bypass, via the auxiliary coolant heater to the first coolant pump, wherein the auxiliary coolant heater is operated. 
     
     
       13. A method of operating the heat pump assembly according to  claim 1  for a reheating mode of a vehicle cabin at ambient temperatures of more than 0° C., wherein a refrigerant releases heat downstream of the compressor in the heating condenser, then a partial flow is expanded in the first refrigerant valve with the expansion function to a medium pressure level and absorbs heat in the ambient heat exchanger, is then expanded in the second refrigerant valve with the expansion function and evaporated in the at least one evaporator with absorption of heat from air and is directed to the compressor, and a partial flow is branched off upstream of the first refrigerant valve with the expansion function and guided, via the ambient heat exchanger bypass, to the third refrigerant valve with the expansion function and is expanded and then evaporated in the chiller and is directed to the compressor, wherein, in the battery coolant circuit, coolant flows from the first coolant pump, via the chiller, the second 3/2-way coolant valve and the battery heat exchanger bypass, via the auxiliary coolant heater to the first coolant pump, wherein the auxiliary coolant heater is operated. 
     
     
       14. A method of operating the heat pump assembly according to  claim 1  for heating a vehicle cabin at ambient temperatures of more than −20° C., wherein a refrigerant releases heat downstream of the compressor in the heating condenser, is expanded in the first refrigerant valve with the expansion function and absorbs heat in the ambient heat exchanger and is then directed to the compressor via the first 3/2-way refrigerant valve and the chiller bypass, wherein the battery coolant circuit and the drive train coolant circuit are connected to each other and the coolant flows from the first coolant pump, via the chiller, the second 3/2-way coolant valve, the battery heat exchanger bypass, the second coolant pump, the drive train cooler and a third 3/2-way coolant valve to the first coolant pump. 
     
     
       15. A method of operating the heat pump assembly according to  claim 1  for heating a vehicle cabin at ambient temperatures of more than −20° C., wherein a refrigerant releases heat downstream of the compressor in the heating condenser, is expanded in the first refrigerant valve with the expansion function and absorbs heat in the ambient heat exchanger and is then directed to the compressor via the first 3/2-way refrigerant valve and the chiller bypass, wherein the battery coolant circuit and the drive train coolant circuit are connected to each other and coolant flows from the first coolant pump, via the chiller, the battery heat exchanger, the first 3/2-way coolant valve, the second coolant pump, the drive train cooler to the first coolant pump. 
     
     
       16. A method of operating the heat pump assembly according to  claim 1  for heating a vehicle cabin at ambient temperatures of more than −20° C., wherein a refrigerant releases heat downstream of the compressor in the heating condenser, then a partial flow is expanded in the first refrigerant valve with the expansion function and absorbs heat in the ambient heat exchanger and is then directed to the compressor via the first 3/2-way refrigerant valve and the chiller bypass, and a partial flow is branched off upstream of the first refrigerant valve with the expansion function and guided to the third refrigerant valve with the expansion function via the ambient heat exchanger bypass and expanded and is then evaporated in the chiller and directed to the compressor, wherein the battery coolant circuit and the drive train coolant circuit are connected to each other and the coolant flows from the first coolant pump, via the chiller, the second 3/2-way coolant valve, the battery heat exchanger bypass, the second coolant pump, the drive train cooler and a third 3/2-way coolant valve to the first coolant pump. 
     
     
       17. A method of operating the heat pump assembly according to  claim 1  for heating a vehicle cabin at ambient temperatures of more than −20° C., wherein a refrigerant releases heat downstream of the compressor in the heating condenser, is then guided to the third refrigerant valve with the expansion function via the ambient heat exchanger bypass and expanded, is evaporated in the chiller and directed to the compressor, wherein the battery coolant circuit and the drive train coolant circuit are connected to each other, and the coolant flows from the first coolant pump, via the chiller, the second 3/2-way coolant valve, the battery heat exchanger bypass, the second coolant pump, the drive train cooler and a third 3/2-way coolant valve to the first coolant pump. 
     
     
       18. A method of operating the heat pump assembly according to  claim 11 , wherein an air PTC is operated to additionally heat the air for the vehicle cabin. 
     
     
       19. A method of operating the heat pump assembly according to  claim 1  for heating a vehicle cabin at ambient temperatures of more than −20° C., wherein a refrigerant releases heat downstream of the compressor in the heating condenser, is then guided to the third refrigerant valve with the expansion function via the ambient heat exchanger bypass and expanded, is evaporated in the chiller and directed to the compressor, wherein the battery coolant circuit and the drive train coolant circuit are connected to each other, and a coolant flows from the first coolant pump, via the chiller, the second 3/2-way coolant valve, the battery heat exchanger bypass, the second coolant pump, the drive train cooler and a third 3/2-way coolant valve and the auxiliary coolant heater to the first coolant pump, wherein the auxiliary coolant heater is operated. 
     
     
       20. A method of operating the heat pump assembly according to  claim 1  for heating a vehicle cabin at ambient temperatures of more than −20° C., wherein a refrigerant releases heat downstream of the compressor in the heating condenser, is then guided to the third refrigerant valve with the expansion function via the ambient heat exchanger bypass and expanded, is evaporated in the chiller and directed to the compressor, wherein, in the battery coolant circuit, the coolant flows from the first coolant pump, via the chiller, the second 3/2-way coolant valve and the battery heat exchanger bypass via the auxiliary coolant heater to the first coolant pump, wherein the auxiliary coolant heater is operated, and wherein, in the drive train coolant circuit, the coolant flows from the second coolant pump, via the drive train cooler, a 3/2-way coolant valve and a drive train loop to the second coolant pump. 
     
     
       21. A method of operating the heat pump assembly according to  claim 1  for heating a vehicle cabin at ambient temperatures of more than −20° C., wherein a refrigerant releases heat downstream of the compressor in the heating condenser and in the ambient heat exchanger, is then expanded in the first 3/2-way refrigerant valve with an expansion function and is evaporated in the chiller and directed to the compressor, wherein, in the battery coolant circuit, a coolant flows from the first coolant pump, via the chiller, the second 3/2-way coolant valve and the battery heat exchanger bypass via the auxiliary coolant heater to the first coolant pump, wherein the auxiliary coolant heater is operated and wherein, in the drive train coolant circuit, the coolant flows from the second coolant pump, via the drive train cooler, a 3/2-way coolant valve and a drive train loop to the second coolant pump.